#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>
#include <sys/mman.h>
#include <math.h>

int main(){

    int a = 0;
    
    a |= (1<<1) + (1<<3);
    printf("a = %d\n", a);

}
